Thread-forming mechanism.



G. T. WARWICK. I THREAD FORMING MECHANISM, .APPLIGATION FILED I1[A1,.l3, 1912v 1,130,226, PatentedMaR Z, 1915.

lVITzVESSES A'TIORNEK 7unrrn sa'rs scenes WARWICK,

'rronar. MACHINE AND SCREW cor/tram, or sramennnn,

CGRPORATION 0F MAINE.

Ta all whom it may concern: I 3 Be it known that 1, Gnoncn T. WARwroK, a citizen. of the United States of America,

t and resident of Springfield, in the county of rolls, to engage Hampden and State of Massachusetts, have invented certainnew and useful Improvements in Thread-Forming Mechanisms, of which the following is a full; clear, and exact description.

This invention relates particularly to mechanism in anbrganized machine that forms screw threads on blanksby engaging the blank between a pair of rolling dies at the adjacent peripheral portion thereof;

which mechanism is automatically brought to engage and support the blank in proper operative position between such rolls; and in timed relation to the revolution of the the blank during the portion of the revolution in which the peripheral surfaces of the roll are forming the threads, and which will retreat to permit removal of the finished blank, and the insertion of a fresh blank.

In the accompanying drawings showing one embodiment of my invention,-Figure 1 is an elevation of a portion only of a thread rolling machine, with the arms in the open position. Fig. 2 shows the same parts with the arms closed on the blank. Fig. 3 is a horizontal section taken through the center of the shaft shown in Fig. 1, and Fig. 4: is a side elevation of the parts shown in Fig. 1.

In the several views, a roll a is shown mounted on a shaft 12, which roll is pro-. vided on its periphery with spiral grooves; and a substantially duplicate threading roll I) is shown that is mounted on a suitable shaft, not shown, but which is parallel with the shaft 12, so as to bring the threaded periphery of the roll 7) adjacent that of the roll a, as indicated in Figs. 1 and 2, the distance apart of these rolls being equal to the diameter of the blank that is engaged between the same, such as the blank S; it being understood that these rolls will be-rotated by suitable means at the same speed and in the same direction, whereby their adjacent peripheral, portions will move in opposite directions at the same surface speed and impart a rotation to the blank, as well understood in this art.

A pair-of movable arms are provided for Specification of Letters were.

these slides in unison iaessacnusi r'rs, A-

THREAD-FORMING MECHANISM.

the purpose of same position between the rolls during the operation, and prevent its being advanced by the arms are held with their ends engag-- ing the blank during the portion of the revo-" lution of the roll awhen the thread is being the thread has, been formed; and after Patented Mar.2, 19.15. v

Application filed March 13, 1912. Serial 1V0. 683,469.

retaining the blank Sat the formed the arms are caused to-frec'ede from i such position to. permit removalof the gln'ezilded blank, and the insertion of a' fresh an I A stationary supporting plate25 ispro-H vided in which is a channel 5 concentric with the shaft 12 that carries the roll a, and curved blocks 23 and 2a are mounted to slide in this channel; which blocks carryaat their extremities arms 26 tively, positioned thereon to be brought to engage the blank S between the rolls a and b when the slides are advanced, as indicated in Fig. 2; and when these slides are retracted, the arms will recede from the blank as indicated in Fig. 1, to permit the removal of the finished article and the insertion of a fresh blank.

simultaneously engage recede from the same, I pivoted at 22 on the frame, and having one arm 21 connected to by links 29 and 28 respectively; the other the blocks 23 'and 24.

and 27 respec-.-

550 For the purpose of moving to cause the arms to" the blank S, and. to provide a bent lever arm 20 of the bent lever being connected with a slide 18.

On the shaft 12 is secured a cam 13 having a portion of its periphery between l4 and 15 concentric for the greater portionof the periphery, while the other portion of the periphery between said two points is cut away; and this periphery of the cam is engaged by a roller 17 on the end of the slide 18, which slide is drawn by a spring 19 to retain the roller in constant engagement with the cam.

From this arrangement it will be understood that when the circular portion of the cam engages the roll, the slide will be advanced to the position shown in Fig. 2, that will shift the bent lever to cause the links to advance the two slides and bring the arms 26 and 27 to the closed position in en,-

gagement with the blank, and the arms will be retained in this position during the greater part of the revolution, and this porthe depression in the cam is in engagement with the roll 17, the spring Will advance the slide and through the lever and links Will retract the arms 26 and 27 from the blank, permitting its removal and a fresh blank inserted; and it will be understood that during this part of the revolution of the shaft 12 the rolls a and b will have the idle portion of the periphery at the position occupied by the blank so that no operation thereon will take place. It will thus be seen that these supporting arms are automatically brought to engage a fresh blank immediately after insertion, and will continue to support the blank until it is finished by-the operation of the thread rolling dies; Whereupon the arms are automatically moved away from the blank to permit its removal.

claim:

1. A thread-rolling machine having a pair of coacting thread forming rolls having means on the periphery to roll a thread on a blank placed between the rolls, a pair of arms movable to and from the coacting adjacent portions of the rolls to supportthe blank in roll-engaging position, and means for reciprocating said arms from one of saidrolls in timed relation.

A thread-roll1ng machine having a pair of coacting thread forming rolls having means on the periphery to roll a thread on a blank placed between the rolls, a pair of arms movable to and from the coacting adjacent portions of the rolls to support the blank in roll-engaging position, a cam carried by one of the rolls, a slide that is spring pressed against said cam so as to be reciprocated thereby, and means connecting the slide and said arms, whereby the cam Will advance the arms to engage a blank between the rolls and hold the blank in such position during a portion of the rotation of the rolls, and will .also cause recession of the blank in roll engaging position, a cam car-- ried by one of the rolls, a slide carrying a roller and guided to reciprocate, a spring on the slide for retaining the roller in engagement with the cam, arm connected with said slide, and a pair of links connected to the other arm of the le ver, the links being connected respectively with said arms whereby the arms are moved to and from the blank as the slide is reciprocated by said cam.

4. A thread rolling machine having a pair of coacting thread forming rolls that have means on the periphery to roll a thread on a blank placed between the rolls, a frame member having a channel concentric with one of the rolls, a pair of curved blocks slidable in said channel, an arm carried by each block that is adapted to be brought to engage the blank in its positionfor engage ment by the rolls, a two armed lever pivoted on the frame, a pair of linksconnecting said lever with said blocks respectively, a slide guided for movement in the frame and connected with the other arm of said lever, a roller on the slide, a cam adjacent one of the rolls and engaged by said roller, a spring on the slide for retaining the roller in engagement with the cam, whereby the roller and slide and links to move the arms to and from blank engaging position, and to retain the arms in such position during operation on the blank by a portion of the rolls.

Signed by me at Springfield, Mass, in presence of two subscribing Witnesses.

one. T. WARWIoK.

are reciprocated to swing said lever lVitnesses WM. S. BnLLows, (h It. Dnrsconn.

a bent lever having one the 

